Investigation on coating methods of a self-assembled monolayer on PDMS (poly(dimethylsiloxane)) surface

Abstract

This paper examines PDMS surface treatment methods that can be applied to immobilize a hydrophilic polymer membrane in a PDMS microchannel by covalent bonding. After creating -OH groups on a PDMS surface by UV/ozone treatment, we form SAM on the surface using 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) or 3-(trichlorosilyl)propyl methacrylate (TPM) reagent. Contact angles between a water droplet and SAM-coated PDMS surfaces decreased due to -OH groups generated on the surfaces. The surface functionalized with TMSPMA resulted in the smallest contact angle of 46 degrees. Raman spectroscopy showed that the intensities of Raman shifts were strongest for the surface functionalized with TMSPMA. Overall, functionalizing a PDMS surface with TMAPMA resulted best among the methods examined in this study.